In recent years, the number of terminals for an electrical connector (hereinafter, an electrical connector is sometimes referred to simply as “connector”) for use in the field of automobiles and the like has increased.
Accordingly, there is a known electrical connector having multi-stacked and combined contact housings, wherein each housing accommodates a plurality of terminals aligned side by side in one direction (for example, as disclosed in Japanese Patent Laid-Open No. 2007-95360 and Japanese Patent Laid-Open No. 2011-96397). Each of the stacked contact housings includes a protrusion and an engaging piece to be engaged with this protrusion, formed on its side face. Thus, the vertically aligned contact housings are coupled together when the protrusion of one of the contact housings engages with an engaging piece on the other contact housing.
Moreover, as shown in FIG. 8, there is a known connector 5 in which a lock housing 3 having an arm 2 couples with all stacked contact housings 1.
The arm 2 extends along the side face of the multi-stacked connector housings 1, and has engaging portions that are formed therein at positions corresponding to the respective connector housings 1. The engaging portions of the arm 2 engage with a protrusion and a recess, not shown, formed along each of the connector housings 1. Thus, by engaging the protrusion and the recess of the respective housings 1 on the respective stage with the respective engaging portions of the arm 2, the multi-stacked connector housings 1 are integrally coupled with one another.
However, in the above-mentioned structure, it is difficult to detect when the respective connector housings are not completely engaged with each other, and a known connector may mate with the mating connector when the multi-stacked connector housings are not incomplete engaged with each other. In such a case, the connector housings and the contacts may be deformed, or it is possible that the contacts held on one connector are not correctly mated with the contacts held on the other connector, and thus the both contacts are not electrically connected with each other.